The task of installing a door jamb or window jamb within a wall opening is often difficult. The door jamb or frame must be installed in a near perfect alignment to enable the door hung within it to open, close and swing smoothly. Additionally, a window or door that is even a fraction out of plumb is readily apparent to an observer. Once the casings and moldings have been applied to a window jamb or door jamb, it is difficult and expensive to correct mistakes made during the installation.
Skilled carpenters installing doors and windows continue to employ traditional techniques used for decades. These techniques include centering the window jamb or. door jamb, involving a complicated series of measurements and adjustments using tools such as bubble levels, plumb bobs, framing squares and tape measures. To properly align the window or door, wedge shaped shims are conventionally tapped between the door jamb or window jamb and the wall's structural members to force the door or window jamb into a desired position. Conventional shims, typically made of wood wedges or shingles, are inconsistent in size and shape and thus add to the difficulty of properly installing a door or window jamb. More particularly, these wedge shaped shims are imprecise and without a size standard. Therefore, a shim is needed that accurately and reliably adjusts a door jamb or window jamb within a rough opening in a wall for proper alignment.
Several prior U.S. Patents show devices to aid in the installation of metal door and window frames or jambs. These devices typically damp onto the wall structure adjacent to the installed door or window for the sole purpose of anchoring a metal door jamb to the wall structure. Metal door jambs are not found in residential construction. Residential door and window jambs or frames are often fabricated from wood products. Alternative residential type jamb or frame materials include vinyl, aluminum and wood composite. Residential door and window jambs are typically lighter in construction than the heavy metal door jambs employed in fire rated metal door jamb and window jamb installations. The patented metal door jamb installation aids all fail to provide a device that can be added to a residential door or window jamb to accommodate walls that are crooked or misaligned openings in the wall.
These patents for devices to aid in the installation of metal door jambs are typically similar to the U.S. Pat. No. 3,250,049 to Sklar for an adjustable damping door jamb. The Sklar patent shows a threaded screw actuated movement only for clamping the adjacent wall member. Typically, when doors and windows are installed, a initial crude opening is made in the wall to accommodate the door or window. These "roughed out" openings are often crooked and misaligned. Sklar falls to solve the problem of aligning a door jamb within a wall structure that is crooked or misaligned.
U.S. Pat. No. 3,889,423 to Begin discloses screw operated "shim members" that are integral within a metal door frame. Begin teaches the use of the shims to pull the posts of the door frame outward toward the structure of the adjacent wall. The Begin patented door frame shim member is not able to adjust to a misaligned wall structure and therefore does not fulfil a need for a shim that accommodates a crooked or misaligned wall structure.
U.S. Pat. No. 4,637,183 to Metz shows a two-part shim incorporated within a door or window frame. The shim has one bolt connecting the two parts at an angle. The shim also includes an integral wing for a hinge. The shim legs damp the shim to the wall structure. The Metz shim is unable to adjust the door or window to accommodate a crooked or misaligned wall structure.
U.S. Pat. No. 4,887,407 to Nelson describes an alignment dip for use in a window frame. A screw means is claimed for biasing the base of the alignment clip. Four screws are preferred, to compress a leaf spring positioned between a plate and a bottom wall of the base. The spring adjusts the window frame for a tight and secure fit into an opening. Nelson teaches using the alignment dip for squaring the window and holding it in a plumb position. The Nelson alignment dip is integral within a metal extruded sash of the window. A further need exists for a shim that can retrofit to any window jamb or frame of a standard design.
Another drawback to the Nelson alignment clip is that it also has a very limited range of "biasing" to accommodate a wall opening that is misaligned or crooked. Wall structure is often found to be out of alignment to an extent that the design of the Nelson alignment clip is unable to compensate. Again, the known devices fail to satisfy a need for a shim that can tilt at a significant angle, instead of only a limited bias, to accommodate the wall opening.
Furthermore, the Nelson alignment clip requires an "adjustable tab means" to allow the alignment dip to accommodate wall openings outside the limited range of the "rotation of the screws." This "adjustable tab means" is cumbersome and fails to accommodate windows with which it was not specifically designed for use. Therefore, further a need exists for a shim without an "adjustable tab means" to accommodate a rough wall opening. Additionally, a need exists for a shim that is expandable to significantly adjust to the rough opening in a wall.
Due to the inadequacies of conventional devices, there remains a need for a tiltable and extendable shim that can easily retrofit to a standard door jamb or a window frame, for aiding the square alignment of the door or window jamb within a roughed out opening in a wall structure.